This component (abbreviated as "NxInit") is specifically developed
for NuttX and intended for system initialization. While we have
adopted the Android Init Language among various syntax options,
this is a brand-new implementation—it is not a port or variant of
Android Init.
Refer to the implementation of Android Init Language, consists of five broad
classes of statements: Actions, Commands, Services, Options, and Imports.
Actions support two types of triggers: event and action. Action triggers also
support runtime triggering. Services support lifecycle management, including
automatic restart (at specified intervals), and starting/stopping
individually or by class. Import supports files or directories, and we may
add a static method in the future. The following are some differences:
1. The Android Init Language treats lines starting with `#` as comments,
while we use a preprocessor to handle comments.
2. For action commands, we can omit "exec" and directly execute
built-in apps or nsh builtins.
3. Regarding the property service, users can either adapt it by self or
directly use the preset NVS-based properties.
4. Only part of standard action commands and service options are
implemented currlently.
To enable system/nxinit:
```diff
-CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_INIT_ENTRYPOINT="init_main"
+CONFIG_SYSTEM_NXINIT=y
```
For format and additional details, refer to:
https://android.googlesource.com/platform/system/core/+/
master/init/README.md
Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
